The Fabrication Testpoint Usage and Assembly Testpoint Usage design rules specify which nets require testpoints for bare-board fabrication testing, or in-circuit assembly testing, respectively. The constraints between these two rules are identical.
Default Fabrication and Assembly Testpoint Usage rules exist. You should check whether these rules meet your board requirements and make changes as necessary.
When opening/importing PCB designs created in a release of the software prior to the Summer 09 release, Testpoint Usage rules will become Fabrication Testpoint Usage rules.
Default constraints for the Fabrication and Assembly Testpoint Usage rule.
Required - each target net must have a testpoint assigned. You can further sub-specify whether only a single testpoint is required for each net, or whether a testpoint is to be inserted at each 'leaf' node in a target net (pad/via locations that terminate a route). In addition, you can specify that a target net can have more testpoints, although these must be manually assigned.
Prohibited - each target net must not have a testpoint assigned.
Don't Care - each target net can have a testpoint assigned. It does not matter if a testpoint cannot be assigned to a net.
How Duplicate Rule Contentions are Resolved
All rules are resolved by the priority setting. The system goes through the rules from highest to lowest priority and picks the first one whose scope expression matches the object(s) being checked.
This rule is obeyed by the Testpoint Manager, Autorouter, the Online and Batch DRC, and during output generation.
Fabrication and Assembly Testpoint reports can be configured and generated along with other fabrication and assembly outputs, as part of an Output Job Configuration file (*.OutJob). Use these reports to interrogate the locations of all valid fabrication and assembly testpoints, assigned in the design, respectively.
Use the Testpoint Manager dialog to identify the status of testpoint coverage for each net in a design, both in terms of bare-board fabrication and in-circuit assembly testing.
A DRC report, obtained from running a Batch DRC, can be used to identify each net that fails this rule.